The invention pertains to a torsional vibration damper for a hydrodynamic clutch arrangement.
A torsional vibration damper is, for example, known from U.S. Pat. No. 6,478,127. The torsional vibration damper is installed axially between a flywheel mass element, which is attached to a drive such as the crankshaft of an internal combustion engine, and a housing of the hydrodynamic clutch arrangement, which is realized as a torque converter. The torsional vibration damper is provided with a drive-side damping element, which is connected nonrotatably on one side to the flywheel mass element and connected for rotation in common on the other side by means of elastic elements to the takeoff-side damping element of the torsional vibration damper, the takeoff-side damping element being in functional connection by way of the hydrodynamic clutch arrangement with a takeoff formed by a gearbox input shaft.
In the known torsional vibration damper, the drive-side damping element is fastened jointly with the flywheel mass element to the drive by means of fastening elements, namely, from the side of the hydrodynamic clutch arrangement. Because the fastening elements are no longer accessible after the hydrodynamic clutch arrangement has been installed, it is necessary to provide a way to detach the drive-side damping element from the elastic elements remaining attached to the hydrodynamic clutch arrangement and from the takeoff-side damping element. Providing this separability, however, causes wear-related problems with the axial positioning of the hydrodynamic clutch arrangement, because the free end of the drive-side damping element facing away from the drive and possibly the free end of a bearing journal provided in the radially inside area of the housing of the hydrodynamic clutch arrangement act as axial support for the hydrodynamic clutch arrangement, and both axial supports are provided in positions of relative rotational movement of the components which enter into axial contact with each other. In addition, connecting the torsional vibration damper to the hydrodynamic clutch arrangement in this way permits no axial elasticity of the latter with respect to the drive, so that the axial vibrations which are generated by the drive and which induce wobbling movements in the flywheel mass element with respect to the axis of rotation of the hydrodynamic clutch arrangement are transmitted with little if any damping to the housing of the hydrodynamic clutch arrangement, where, as a result of the fluid filling of the latter, they are considered especially critical.
It is known from U.S. Pat. No. 6,298,965 that a drive can be connected by way of a drive plate which is flexible in the axial direction to a drive-side damping element of a torsional vibration damper and from this via elastic elements and a takeoff-side damping element to the housing of a hydrodynamic clutch arrangement. As a result of the flexible drive plate, referred to in brief below as a flexplate, axial vibrations of the drive can be effectively kept away from the housing of the hydrodynamic clutch arrangement. Because of its location effectively between the drive and the torsional vibration damper, however, this flexplate prevents the realization of a direct connection between the hydrodynamic clutch arrangement and the drive in the event that the torsional vibration damper is omitted. Thus, this solution is not very versatile with respect to applications in the automobile industry, where it is known that frequently changing requirements call for constant adaptation to specific demands.